Kaepernick, starting in place of Alex Smith, was 16-of-23 passing for 243 yards and two touchdowns with a 133.1 passer rating. He wasn't perfect, but Kaepernick showed he can handle himself on an NFL field. It was a solid game for a second-year quarterback.

1. Kaepernick is more than just a gadget quarterback

There's a good chance Kaepernick might even be the Niners' QB of the near future. Smith hasn't been mistake-prone, but no one is reminded of great 49ers quarterbacks with the way he plays. He might not even rate in the same class as Jeff Garcia.

Kaepernick, on the other hand, displayed great physical skills and the kind of mobility the 49ers had in Steve Young. But what he showed against the Bears that no one had seen to this point was a real understanding of the offense.

Example: He was able to audible into and out of runs, burning the Bears when they blitzed with his arm and legs. He picked out secondary receivers, and he out-thought a veteran defense that has been near the top of the league all season.

"I think after the first drive I felt really comfortable with what they were doing and what we had in our game plan," he said. "I really wasn't too nervous. I've had a lot of time in this offense. My teammates were really supportive."

It was the kind of performance the 49ers envisioned when they traded up to take him the 2011 Draft's second round.

"It's everything I could've ever wished for," Kaepernick said. "It feels great just to be out there."

So which way will coach Jim Harbaugh go when Smith is healthy?

"I usually tend to go with the hot hand, and we've got two quarterbacks with hot hands," he said. "We'll make that decision when we have to make it."

2. Niners defense could be golden

Yeah, Frisco defenders have had more than their share of slip-ups — the 26-3 slaughter at the hands of the New York Giants and allowing 24 points to the St. Louis Rams in a tie.

But with the season getting closer to the stretch run, that defense appears to be reaching the level of dominance it displayed through most of last season. A hard-hitting linebacker corps and the pass-rushing ferocity of the so-called Smith brothers kept the Bears backing up throughout the first half in helping establish a 20-0 lead. Not much changed in the second half.

The 49ers figure to get two good tests down the stretch, one next week against the New Orleans Saints and then Dec. 16 on the road against the New England Patriots — in what could be a Super Bowl preview.

Aldon Smith took over the NFL sacks lead with 15, two more than the Denver Broncos' Von Miller. Tarell Brown and Dashon Goldson each had an interception.

"I think I have a thing for night games, I love playing at night," Smith said. "I love playing under the lights."

3. Protection scam

A porous offensive line makes it difficult for anyone to take the Bears more seriously than a one-and-done if they make the playoffs.

Now tied with the Green Bay Packers, and with the Packers owning the tiebreaker, the Bears haven't established anything beyond the fact they can force the ball to wide receiver Brandon Marshall. Why? Largely because they can't block anyone.

Monday showed that it might have been Jay Cutler's mobility and ability to hook up with Marshall that was making the offensive line look better than it was. It also calls into question Mike Tice's effectiveness as an offensive coordinator-line coach.

When Tice was offensive line coach only, he molded his players a bit and gave Cutler and the running game a little time and room to operate. This season the line and the offense have achieved nothing with Tice in charge.

Like Smith, Cutler was injured and didn't play. It was Jason Campbell directing the offense. Result: Campbell was 14-of-22 passing for 107, a touchdown and two interceptions.

"Tonight was probably the worst nightmare. We just have to find a way," Campbell said. "It's one game that we lost. We have to pick it back up next week and try to get back on the winning side. Our goals and everything still sit ahead of us."